... only after the second year of life [4,8,9]. By the age of 4 years, the average cranial extent of the frontal sinus reaches half the height of the orbit and extends just above the top of the ... Embryology, Development and Anatomy of the Nose, Paranasal Sinuses, Nasolacrimal Passageways and Ol-factory Organs in Man. Philadelphia: P Blakiston’s Son; 1920. 8. Som PM, cCurtin HD. Head and ... study evaluated the DVT images using DVT software (Quantitative Radi-ology, NNT Software version 2.21, Verona, Italy) with respect to aplasia and agenesis of the frontal sinus on coronal images...